TROUBLESHOOTING

In the event of a malfunction (burning smell, etc.), immediately stop operation, disconnect the

WARNING! Power Supply Plug, and consult authorized service personnel.

Merely turning off the unit’s power switch will not completely disconnect the unit from the power source. Always be sure to disconnect the Power Supply Plug or turn off your circuit breaker to ensure that power is completely off.

Before requesting service, perform the following checks:

 

Symptom

Problem

See Page

 

 

 

 

NORMAL

Doesn’t operate immedi-

● If the unit is stopped and then immediately started again, the com-

 

FUNCTION

ately:

pressor will not operate for about 3 minutes, in order to prevent

 

 

 

fuse blowouts.

 

 

● Whenever the Power Supply Plug is disconnected and then re-

 

 

 

 

 

connected to a power outlet, the protection circuit will operate for

 

 

 

about 3 minutes, preventing unit operation during that period.

 

 

 

 

 

 

Noise is heard:

● During operation and immediately after stopping the unit, the

 

 

 

sound of water flowing in the air conditioner’s piping may be

 

 

 

heard. Also, noise may be particularly noticeable for about 2 to 3

 

 

 

minutes after starting operation (sound of coolant flowing).

 

 

● During operation, a slight squeaking sound may be heard. This is

 

 

 

the result of minute expansion and contraction of the front cover

 

 

 

due to temperature changes.

 

 

 

 

 

 

 

● During Heating operation, a sizzling sound may be heard occasional.

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This sound is produced by the Automatic Defrosting operation.

 

 

 

 

 

 

 

 

Smells:

● Some smell may be emitted from the indoor unit. This smell is

 

 

 

the result of room smells (furniture, tobacco, etc.) which have

 

 

been taken into the air conditioner.

 

 

 

 

 

 

Mist or steam are

● During Cooling or Dry operation, a thin mist may be seen emitted

 

 

emitted:

from the indoor unit. This results from the sudden Cooling of

 

 

room air by the air emitted from the air conditioner, resulting in

 

 

 

condensation and misting.

 

 

 

 

 

 

 

● During Heating operation, the outdoor unit’s fan may stop, and

 

 

 

steam may be seen rising from the unit. This is due to Automatic

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Defrosting operation.

 

 

 

 

 

 

Airflow is weak or stops:

● When Heating operation is started, fan speed is temporarily very

 

 

 

low, to allow internal parts to warm up.

 

 

 

● During Heating operation, if the room temperature rises above

 

 

the thermostat setting, the outdoor unit will stop, and the indoor

 

 

 

unit will operate at very low fan speed. If you wish to warm the

 

 

 

room further, set the thermostat for a higher setting.

 

 

 

 

 

 

 

● During Heating operation, the unit will temporarily stop opera-

 

 

 

tion (between 7 and 15 minutes) as the Automatic Defrosting mode

14

 

 

operates. During Automatic Defrosting operation, the OPERATION

 

 

 

 

 

Indicator Lamp will flash.

 

 

 

 

 

 

 

● The fan may operate at very low speed during Dry operation or

5

 

 

when the unit is monitoring the room’s temperature.

 

 

 

 

 

 

 

 

 

● During SUPER QUIET operation, the fan will operate at very low

5

 

 

speed.

 

 

 

 

 

 

 

 

 

● In the monitor AUTO operation, the fan will operate at very low

5

 

 

speed.

 

 

 

 

 

 

 

 

Water is produced from

● During Heating operation, water may be produced from the out-

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the outdoor unit:

door unit due to Automatic Defrosting operation.

 

 

 

 

 

 

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Fujitsu ASU18RL, AOU18RL operation manual Troubleshooting, Symptom Problem